Cartons



Feb. 13, 1962 s. R. PHIN 3,021,043

CARTONS Filed Juhe 16, 1958 INVENTUR SYDNEY R. PHIN United States This invention relates to improvements in cardboard or paperboard containers, cartons or the like, and part1cularly to scalable containers or cartons for the packaging of products which include liquids or which are relative- 1y free flowing.

In the packaging of such products in cardboard or paperboard containers, difliculty is experienced in achiev ing and adequate seal at the corners of the container or carton to prevent spillage or seepage of the product. This problem is especially acute following the filling of the container and before final sealing and usually necessitates that the container be oriented in an upright position until the final seal.

Further, with present containers of this nature, opening is effected by a knife or the like, and once the container is opened there is normally no effective way of reclosing it so that the unused contents can be preserved or stored, particularly where such contents are liquid in nature without danger of spillage.

It is an important object of this invention to provide a container or carton formed of cardboard, paperboard or the like which will enable a liquid proof seal to be effected at the corners, and will enable the container after being filled to be heat sealed or overwrapped while on its side. More particularly, it is an object to provide a container or carton as aforesaid which preferably can be formed and closed by heat sealing.

Another important object is to provide a container or carton which can be quickly and easily opened without requiring the destruction of either the carton or its closure so that the carton can be eifectively reclosed to contain and preserve any remaining contents and can be stored while fiat on its side even when such contents are liquid without spillage of the contents.

Still another important object is to provide a container or carton as aforesaid of very simple and economical construction which can be very easily closed and sealed, for instance, by heat sealing.

Still a further important object is to provide a container or carton having a planar exterior surface for carrying printed matter. In particular, it is an object to provide a planar bottom or end panel which will be entirely available for the reception of printed material.

According to one important aspect of the invention, the closure for the carton comprises a top flap joined at each end to both of the end walls and one side wall by a gusset which permits closing of the top flap, yet provides an uninterrupted liquid retaining barrier at the juncture of such side wall, top flap and end walls with the carton disposed on such side wall and the closure flap partially open allowing the carton contents to be retained with the carton on its side. In this connection, a further feature resides in utilizing the connection afforded by the gussets as a means of retaining the top flap in partially closed position while the carton is on its side.

Another important feature resides in providing the top flap with a tuck-in, and according to one embodiment of the invention utilizing such tuck-in, preferably in addition to a quick opening tab, as a means of temporarily sealing the carton. According to another form of the invention, where the carton is not required to be fully liquid proof, the top flap tuck-in is arranged to cooperaice tively interlock with the free edges of the gussets to provide a positive top flap interlock.

Still another important feature resides in forming the container or carton so that the end walls are formed of a pair of overlapping end wall flaps carried by the opposing side Walls, and the bottom of the container is provided with end tabs or flaps which are adapted to interfit with and lie in the same plane as the inner pair of end wall flaps so that the sealing of the overlapping outer end, wall flaps to the underlying flaps and interfitting bottom flaps seals the lines of interfit between such flaps and effectively seals the bottom corners of the carton.

In this connection, by arranging the bottom tabs or flaps to lie coplanar with the underlying under wall flaps, the bottom, end and side walls are each rendered planar, thereby greatly facilitating the application of printing and advertising material thereto.

According to the invention, the carton is preferably formed from cardboard, paperboard, or the like, which is coated either on one side or both sides with a suitable coating such as a suitable polyethylene and wax combination, a suitable vinyl or a suitably vinyl and wax combination, which will render it impervious to moisture and enable the surfaces thereof to be heat sealed together when assembled to bring opposing surfaces into face to face relation.

These and other objects and features of the invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a plan view of a typical form of blank from which a carton or container embodying the invention may be formed;

FIGURE 2 is an end elevational view of the blank of FIGURE 1, partially folded into carton forming relation;

FIGURE 3 is a perspective view illustrating the blank of FIGURE 1 further assembled into carton forming relation;

FIGURE 4 is a fragmentary enlarged perspective view illustrating one of the gussets joining the topclosure or flap With one side and end wall; I

FIGURE 5 is a perspective view of the completed carton;

FIGURE 5A is a fragmentary perspective view showing details of the seal between the top closure, gussets and side wall;

FIGURE 6 is a fragmentary plan view showing a blank for forming an alternative form of carton;

FIGURE 7 is a fragmentary perspective view illustrating an alternative form of carton formed up from the 'bllankd of FIGURE 6 with the top closure ready to be c ose FIGURE 8 is a fragmentary plan detail illustrating the interlock between the top closure and one of the connecting gussets.

With reference to FIGURE 1, the blank 1 is showncut and scored to provide panels 2 and 3 which in the fin-Q" ished carton are to define or comprise side walls of the carton, a bottom wall defining panel 4, and a top closure flap 5. The side wall defining panel 2 is provided with end flaps 6 of rectangular form, while the panel 3 is provided with end flaps 7 which are cut on the bias at 8 adjacent to the bottom wall defining panel 4. The bottom wall panel 4 is provided with triangular tabs 9 which are adapted to cooperate with the end flaps 7 as hereinafter more fully described.

The top closure or flap 5 is joined to theend flaps 6 by corner pieces designated at 12 defined by score lines 10 and 11, and these corner pieces are creased or scored on the diagonals indicated at 13 so that when the corners 12 are folded into carton forming relation they. form gussets. The top closure or flap is provided with an edge extension 14 having centrally thereof a pull tab 15.

The blank 1 may be formed of any suitable material such as cardboard or paperboard of the requisite weight or thickness, and preferably it is coated with a suitable thermoplastic heat sealing compound such as polyethylene or vinyl with or without wax combinations. Preferably both sides of the blank 1 are coated, although in certain instances one side only may be coated. In the forming of the carton from the blank, the end flaps 7 of the side wall panel 3 and the triangular tabs 9 are folded into coplanar relation with the tabs 9 filling the corners of the flaps 7 cut oil. by the bias cut lines 8 as shown in FIG- URE 2. Following this step, the coplanar end flaps 7 and triangular tabs 9 are inserted between the folded end flaps 6 carried by the side wall panels 2, and it will be seen that these flaps 6 will overlie and will everywhere be contiguous with the fiaps 7, whereupon the end flaps 6 and 7 and tabs 9 are heat sealed together to form an end wall structure having a double thickness of material. In this connection, by virtue of the lamination effect provided at the end walls formed by the flaps 6 and 7 and tabs 9, a substantial measure of rigidity is imparted to the carton allowing a relatively thin material to be used in the manufacture of the carton. Moreover, it will be apparent that the efiect of the heat seal, the coplanar relation of the tabs 9 and flaps 7 and the overlapped relation of the flaps 6 with such latter members will provide an intimate and liquid tight seal at the bottom corners 16 of the carton, and there will be no thickness of material preventing such an intimate liquid tight corner seal as would be the case if the tabs 9 were folded over the end flaps 7 rather than being coplanar therewith. Further, of course, the sealing of the flaps 6 in the overlapped relation will seal the bias cut lines 8.

Also in this connection, by arranging the bottom tabs or flaps to lie coplanar with the underlying under wall flaps, the bottom, end and side walls are each rendered planar, thereby greatly facilitating the application of printing and advertising material thereto.

With the carton assembled to this position, it will be seen that the carton may be supported on its side 2, and even with the top closure or flap 5 partially open, it will retain liquid since the intimate bottom seals will prevent spillage or seepage at the bottom of the container and the gussets 12 which join the top closure or flap 5, the side wall 2, and the flaps 6, provide an uninterrupted barrier which will prevent egress or ingress of liquid at the corners 17. Further, these gussets upon being folded serve to retain the top flap 5 in a partially closed relation.

Upon filling of the carton, it is closed by folding the edge extension 14 down onto the side wall 3, and sealing this edge extension to the edges of the gussets 18 opposite to the corners 17 and to the side wall 3 as best shown in FIGURE 5A. Preferably the seal between the extension 14 and the side 3 is merely a line seal which is considerably weaker than the seal between the flaps 6 and 7 and tabs 9, so that it forms a more or less temporary seal which will enable the top flap to be opened readily upon pulling on the pull tab 15 to break this line seal, and the line seal is effected between the edges 18 of the gussets and the extension 14 without either tearing the material from which the carton is formed, or rupturing the remaining carton seals.

The sealing of the top flap extension 14 to the gusset edges 18 provides an effective liquid tight seal at the uppe corners 19 opposite to the corners 17.

After the carton has been opened by breaking the temporary seal between the top flap edge extension 14 and the side wall 3 and gusset edges 18, and it is desired to reclose the carton, the edge extension 14 provides a tuckin feature achieved by forcing the extension between the upper gusset edges 18 and the inner face of the side wall 3 to provide a frictional interlock resisting removal of the extension and opening of the top flap.

In the embodiment of the invention illustrated in FIG- URES 6 to 8, a blank similar to the blank 1, but of slightly modified form, is designated at 1. The only dilference between the blank 1 and the blank 1 is in the formation of the corner pieces 12' which ultimately are to form the gussets connecting the top closure or flap 5 to the side wall 2' and end flaps 6'. As shown, these corners 12 are notched as at 29, and further, the top flap edge extension 14 is slit in from the ends as indicated at 21. Thus, when the carton is formed up from the blank 1 as illustrated in FIGURE 7, the notched portions 20 of the gussets 12 are arranged to receive the edge extension 14' and the double wall formation, the upper edges of which are designated at 18' in FIGURE 8, of the gussets, are adapted to be received in the slits 21 to interlock behind the edge extension 14' and retain it against accidental removal, either initially or on reclosure of the top flap 5'.

It will be understood that, where desired, overwraps may be used with cartons constructed in accordance with the invention. For instance, it will be understood that, while the carton illustrated in respect of the embodiment of the invention shown in FIGURES 1 to 5 may be conveniently sealed to provide a liquid tight or a liquid impervious carton, nevertheless it may still be desirable to overwrap the carton with any suitable material.

It will be understood that the carton, for instance, shown in the embodiment illustrated in respect of FIG- URES 6 to 8, can equally as well be filled with a substance, for instance, a food such as strawberries, oysters or the like, having a liquid associated therewith and then placed on one side without danger of spillage. However, in this case, the mechanical interlock afforded by the interengagement of the extension 14 behind the gusset edges 18' will not be as effective as the liquid tight seal afforded at the corners 19 of the carton of FIGURE 5. Nevertheless, a secure liquid seal may readily be effected after filling by using a suitable overwrap.

It will be understood that various modifications in the actual details of the blank may be made without departing from the spirit of the invention or scope of the appended claims. For instance, it will be understood that while the triangular tabs 9 are of a convenient shape for accomplishing an interfit with the end flaps 7 so that these flaps and tabs are in coplanar relation, other complementary shapes may obviously be employed. The tab 15, for instance, can then be temporarily sealed to the side 3 of the carton to secure the scaled extensions in position corresponding to FIGURE 5.

It will also be understood that various other modifications obvious to those skilled in the art may be resorted to, and the cartons herein depicted are to be considered as merely illustrations of the preferred form of the invention.

What I claim as my invention is:

1. In a carton formed from a material having a heat scalable coating thereon, a pair of spaced parallel side wall panels, each having a top edge, end edges and a bottom edge, and a bottom wall panel joining the bottom edges of said side wall panels, the bottom wall having end edges registering with the end edges of said side wall panels, each of said side wall panels having a flap portion along the entire extent of'each of its end edges, and said bottom wall panel having a flap portion along the entire extent of each of its end edges, the side wall flap portions and bottom wall flap portion at each end being overlapped and heat sealed together to define a liquid tight end wall formation with liquid tight bottom corners, one of the side wall flap portions and bottom wall flap portion of each end wall formation being arranged and having a configuration to fit together in co-planar relation and the other of said side wall flap portions of each end wall formation having an extent to overlap with and bridge the juncture between said co-planar side wall flap portion and end wall flap portion.

2. A carton as claimed in claim 1 in'which a top closure is provided comprising a top flap connected along the entire extent of the upper edge of the side wall panel whose flap portions comprise the outer of said overlapped side wall fiap portions, and to the upper edges of said latter mentioned outer side wall flap portions respectively by means of gussets forming uninterrupted liquid tight wall barriers at the corners defined by the juncture of said end wall formations, said latter side wall panel and said top flap.

3. A carton according to claim 2 in which the coplanar side wall flap portion and bottom wall flap portion are disposed inwardly of the side wall flap portion overlapping and bridging the juncture between same.

4. A carton as claimed in claim 2 in which said top flap has an extension along its free edge adapted to overlie the side wall panel whose flap portions comprise the inner of said overlapped flap portions, said extension being adapted to be heat sealed to said latter side wall panel.

5. In a carton, a pair of spaced parallel side wall panels, each having a top edge, end edges and a bottom edge, and a bottom wall panel joining the bottom edges of said side wall panels, the bottom wall having end edges registering with the end edges of said side wall panels, each of said side wall panels having a fiap portion along the entire extent of each of its end edges, and said bottom wall panel having a flap portion along the entire extent of each of its end edges, said side wall flap portions and said bottom wall flap portion at each end being overlapped and secured together to define an end wall formation, one of the side wall flap portions and bottom wall flap portion of each end wall formation being arranged and having an extent and configuration to fit together in co-planar relation and the other of said side wall flap portions of each characterized in that each of said bottom wall flap portions has a configuration of a right-angle triangle and each of said co-planar side wall flap portions has a lower biased edge registering with the edge defining the hypotenuse of the triangularly shaped bottom wall flap portion.

6. A carton as claimed in claim 5 in which a top closure is provided comprising a top flap connected along the entire extent of the upper edge of the side wall panel whose flap portions comprise the outer of said overlapped side wall flap portions and to the upper edges of said latter-mentioned outer side wall fiap portions respectively by means of gussets forming uninterrupted liquid tight barriers at the corners defined by the juncture of said end wall formations, said latter side wall panel and said top flap.

References Cited in the file of this patent UNITED STATES PATENTS 362,583 Jordan May 10, 1887 1,989,659 Adsit et a1 eb. 5, 1935 2,002,005 Gottlieb May 21, 1935 2,014,335 Kilmer et al Sept. 10, 1935 2,288,056 Wentz June 30, 1942 2,465,949 Williamson Mar. 29, 1949 2,577,007 Dubilier Dec. 4, 1951 2,649,672 Thompson Aug. 25, 1953 2,704,179 Wilcox Mar. 15, 1955 2,902,204 Moore Sept. 1, 1959 

